LAUSR

Abstarct We perform systematic first-principles calculations to clarify the effects of the cluster Mn-X6 (X=P, S, Cl, Br or Te) doping on the structural, electronic, magnetic and optical properties of monolayer WSe2. The smaller formation energy shows that all doping systems are more stable under W-rich condition than Se-rich condition. The cluster Mn-S6 doped monolayer WSe2 has the smallest formation energy may be due to S and Se elements having similar electronegativity, while the maximum formation energy of the cluster Mn-Te6 doping may be due to the lowest electronegativity of the Te element. Although pure monolayer WSe2 is a non-magnetic semiconductor, the Mn-P6 and Mn-Te6 doped monolayer WSe2 become magnetic semiconductor, while the Mn-S6, Mn-Cl6 and Mn-Br6 doped monolayer WSe2 turn into magnetic half-metal. Compared with the pure monolayer WSe2, the cluster Mn-X6 doped monolayer WSe2 have not only a red-shift phenomenon but also an enhanced absorption in infrared and far-ultraviolet region and thus a potential application in infrared and far-ultraviolet light detectors.